一、儲能變流器是雙向還是單向

儲能變流器（PCS）又(you)稱儲(chu)能(neng)逆變器，是連接儲(chu)能(neng)電(dian)(dian)池系(xi)統和電(dian)(dian)網的雙(shuang)向電(dian)(dian)流可(ke)控(kong)轉換(huan)裝置，能(neng)夠在電(dian)(dian)網和儲(chu)能(neng)系(xi)統間精(jing)確快速地(di)調(diao)節電(dian)(dian)壓(ya)、頻率、功率，實現恒功率恒流充放電(dian)(dian)以及平滑波動性(xing)電(dian)(dian)源輸(shu)出(chu)。

儲能變(bian)流器不僅能滿足(zu)傳統并網(wang)變(bian)流器對(dui)(dui)直流電(dian)轉換為(wei)交(jiao)流電(dian)的逆變(bian)要求，還(huan)可(ke)滿足(zu)儲能系統“充電(dian)+放電(dian)”帶來的雙(shuang)向(xiang)變(bian)流需(xu)求，具有對(dui)(dui)電(dian)池充電(dian)和放電(dian)功能，可(ke)用于光伏、風力(li)發電(dian)功率平滑、削峰填(tian)谷、微型電(dian)網(wang)等多種場合。

并網模式下，在(zai)負荷(he)低(di)谷期(qi)，儲能變(bian)流(liu)(liu)(liu)器把電(dian)網的(de)交(jiao)流(liu)(liu)(liu)電(dian)整流(liu)(liu)(liu)成直流(liu)(liu)(liu)電(dian)給(gei)電(dian)池組充(chong)電(dian)，在(zai)負荷(he)高峰期(qi)，儲能變(bian)流(liu)(liu)(liu)器把電(dian)池組中的(de)直流(liu)(liu)(liu)電(dian)逆變(bian)成交(jiao)流(liu)(liu)(liu)電(dian)反(fan)送到電(dian)網中。

離網模式下，儲(chu)能(neng)變流器與主電(dian)網脫開，給本地(di)的部分負荷提(ti)供滿足電(dian)網電(dian)能(neng)質量要求的電(dian)能(neng)。

二、雙向儲能變流器的工作模式有哪些

雙向儲能變流器pcs的工作模式分(fen)為并網模式、離網模式和混(hun)合模式。

1、并網模式

并(bing)(bing)網(wang)模(mo)式下(xia)包括(kuo)充電(dian)(dian)功能(neng)(neng)和(he)放電(dian)(dian)功能(neng)(neng)，此(ci)時(shi)用(yong)(yong)戶可以(yi)選(xuan)擇自動(dong)(dong)模(mo)式和(he)手動(dong)(dong)模(mo)式。在(zai)(zai)自動(dong)(dong)模(mo)式下(xia)，如果(guo)用(yong)(yong)戶選(xuan)擇并(bing)(bing)網(wang)充電(dian)(dian)或(huo)放電(dian)(dian)狀態，儲能(neng)(neng)逆(ni)變器將以(yi)之前設定(ding)好的(de)值對(dui)蓄電(dian)(dian)池進行充電(dian)(dian)或(huo)放電(dian)(dian)。在(zai)(zai)手動(dong)(dong)模(mo)式下(xia)，用(yong)(yong)戶可以(yi)通過手動(dong)(dong)修改充電(dian)(dian)或(huo)放電(dian)(dian)電(dian)(dian)流(liu)、電(dian)(dian)壓和(he)時(shi)間(jian)值，使儲能(neng)(neng)逆(ni)變器工作在(zai)(zai)設定(ding)的(de)充電(dian)(dian)或(huo)放電(dian)(dian)狀態。

并網模式中，儲能逆變器連接在一個大容量公用電網中，大容量是指該電網的總容量至少比儲能逆變器容量大10倍以上。并網模式的主要特征是儲能逆變器必須與存在的電(dian)網頻率同步(bu)。要做(zuo)到與電(dian)網同步(bu)，儲能(neng)逆(ni)變(bian)器(qi)相(xiang)對于(yu)電(dian)網來說(shuo)作為(wei)一(yi)個電(dian)流源(yuan)。有(you)些情(qing)況下(xia)，儲能(neng)逆(ni)變(bian)器(qi)必須能(neng)通過無功控制(zhi)為(wei)電(dian)網提供電(dian)壓支持。該(gai)模式常用(yong)于(yu)削峰填谷、電(dian)力負(fu)載平衡和調節電(dian)能(neng)質量。

2、離網模式

孤島系(xi)(xi)統(tong)是一(yi)個或(huo)多個發電(dian)(dian)(dian)(dian)(dian)(dian)系(xi)(xi)統(tong)并聯形成一(yi)個局(ju)(ju)(ju)部(bu)(bu)的(de)“微(wei)網(wang)(wang)”。孤島系(xi)(xi)統(tong)的(de)主要特征是局(ju)(ju)(ju)部(bu)(bu)電(dian)(dian)(dian)(dian)(dian)(dian)網(wang)(wang)與(yu)所有的(de)大電(dian)(dian)(dian)(dian)(dian)(dian)網(wang)(wang)脫(tuo)離(li)，儲(chu)能系(xi)(xi)統(tong)的(de)額定功率(lv)(lv)與(yu)局(ju)(ju)(ju)部(bu)(bu)電(dian)(dian)(dian)(dian)(dian)(dian)網(wang)(wang)產生的(de)總(zong)功率(lv)(lv)大致相等。在這個系(xi)(xi)統(tong)中，儲(chu)能系(xi)(xi)統(tong)必須可以充(chong)當(dang)網(wang)(wang)路電(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)，給局(ju)(ju)(ju)部(bu)(bu)電(dian)(dian)(dian)(dian)(dian)(dian)網(wang)(wang)提供電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)和頻率(lv)(lv)控制(zhi)。另(ling)一(yi)方面，如(ru)果一(yi)個發電(dian)(dian)(dian)(dian)(dian)(dian)裝(zhuang)置(zhi)不能與(yu)其他(ta)發電(dian)(dian)(dian)(dian)(dian)(dian)裝(zhuang)置(zhi)同步，比如(ru)一(yi)個柴油發電(dian)(dian)(dian)(dian)(dian)(dian)機連接在局(ju)(ju)(ju)部(bu)(bu)電(dian)(dian)(dian)(dian)(dian)(dian)網(wang)(wang)上，那么儲(chu)能系(xi)(xi)統(tong)必須作為(wei)一(yi)個電(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)之同步。有些情況下，儲(chu)能系(xi)(xi)統(tong)還要在作為(wei)電(dian)(dian)(dian)(dian)(dian)(dian)源(yuan)和與(yu)發電(dian)(dian)(dian)(dian)(dian)(dian)裝(zhuang)置(zhi)同步之間轉(zhuan)換。

孤(gu)島(dao)系(xi)(xi)統的特征是儲(chu)能(neng)(neng)系(xi)(xi)統與局(ju)部電網相連，這些情形可能(neng)(neng)存在(zai)于(yu)偏遠山區或小島(dao)嶼。常見(jian)應用(yong)包括(kuo)平滑由可變電源(yuan)可變負載引起的功率波動，穩定電網，優化(hua)燃料的使用(yong)和調節電能(neng)(neng)質量。

3、混合模式

儲能(neng)系(xi)(xi)統能(neng)夠在并網(wang)(wang)(wang)模式和(he)離網(wang)(wang)(wang)模式之間進行(xing)切換。儲能(neng)系(xi)(xi)統處于微(wei)(wei)網(wang)(wang)(wang)中，微(wei)(wei)網(wang)(wang)(wang)與公(gong)共電網(wang)(wang)(wang)接，正常工作狀態下作為并網(wang)(wang)(wang)系(xi)(xi)統運行(xing)如果微(wei)(wei)網(wang)(wang)(wang)與公(gong)共電網(wang)(wang)(wang)脫(tuo)離，儲能(neng)系(xi)(xi)統將(jiang)工作在離網(wang)(wang)(wang)模式為微(wei)(wei)網(wang)(wang)(wang)提(ti)供主電源(yuan)。常見應用包括濾波，穩(wen)定電網(wang)(wang)(wang)，調節(jie)電能(neng)質量(liang)和(he)創造自愈網(wang)(wang)(wang)。